Potential for Using Biogeochemical Markers to Assess and Monitor the Impact of Military Training Exercises on Desert Ecosystems: Proof-of-Concept.
Abstract
The rate of nitrogen fixation and nitrogen flux in soil samples collected from a pristine and heavily disturbed site at Marine Corps Air Ground Combat Center (MCAGCC) Twenty-Nine Palms were 6 +/- 2.05 and 3 +/- 1.04 mM ethylene/g-h and 30.1 +/- 6.47 and 21.9 +/- 6.95 micrograms/sq m - d respectively (P </= 0.05). In addition, significantly more bacteria are present in the disturbed soil samples and principle component analysis demonstrates distinct differences in the bacteria at each site. These data can be interpreted in terms of the destruction of vegetation and release of nutrients that accompany military training exercises. Decay of damaged vegetation releases nutrients that support bacterial growth and suppresses nitrogen-fixing bacteria. The bacteria at the disturbed site also appear to be experiencing an increase in environmental stress that may be associated with the damaged vegetation, soil compaction, reduced percolation of water, and/or a decrease in oxygen in the soil gas. A solid state ammonia sensor constructed by American Research Corporation of Virginia and tested in desert soil detected ammonia concentrations as low as 20 ppb which is the concentration reported for desert soils in this and other studies.
Document Details
- Document Type
- Technical Report
- Publication Date
- Sep 01, 1999
- Accession Number
- ADA369688
Entities
People
- Frederick E. Goetz
- Leslie Karr
Organizations
- Naval Facilities Engineering Service Center